Humidifier unit



M. A. PWERs .E1-AL 2,847,989

-ugn 19, 1958 l HUMIDIFIER UNIT y 2 Smets-sheer 1 AFiled. June 17. 1954 muMuH M Hs/ INVENToRs M/L ro/v A Powees By Poes C. CHM/UN Aug 19, 1958 M.l A. Fowl-:Rs ETAL 2,347,989 I HUMIDIFIER UNIT 2 sheets-sha1 2 Filed June 17. 1954 www T5 WKM VWM mnmC. mm C r mn mm m Mon M HUMIDIFIER UNIT Milton A. Powers and Robert C. Champlin, Detroit, Mich., assignors to Shuttle Manufacturing Company, Milford, Mich., a corporation of Michigan Appiication June 17, 1954, Serial No. 437,442

Claims. (Cl. 126-113) The present invention relates to improvements in an air humidifier whereby it can be conveniently mounted on the side wall of any size or shape of warm air furnace, floor furnace, space heater, air duct or the like, said humidifier being characterized by the extremely effective manner in which it humidiiies the air stream.

Until the recent developments disclosed in the copending applications of Powers, serial No. 334,469, liled February 2, 1953, from which Letters Patent No. 2,740,396 was granted April 3, 1956, and Serial No. 335,720, liled February 9, 1953, now abandoned, it was conventional practice to install humidilier units in such a manner that the pan extended into the air stream thereby constituting a serious obstruction of the air liow, particularly adjacent the evaporating plates or elements. This undesirable feature of the prior art devices prevented effective humidification of the air and prevented the most eflicient operation of modern furnaces as is explained in the aforesaid applications. Evaporating pans, heretofore, even when reduced to minimum effective size always introduce some obstruction to the air ow inside a furnace. Furthermore, in practically all cases it has been necessary to install the unit in the yair space above the inner heating chamber of the furnace, as in addition to operating in heated air, actually there is no other area with sufficient space to physically receive the unit. It is universal practice to design furnaces with an air space of at least six inches between heating chamber and outer wall through which the air being heated flows. Usually a sheet metal, inner liner also occupies this space.

midiiier anywhere in such side walls of the furnace. With the present invention it is now easily possible to install the humidifier in any side wall of any furnace. lt is only necessary to v'select the best position, cut an aperture in the outer wall, cut also an aperture adjoining in the inner liner if it is too close to clear the plates, and complete the installations.

Furthermore, as it is attempted to install humidiiiers in the increasing large number of smaller homes, where extremely limited space is available for the furnace in any case, and where furnaces are placed in tight closets, under stairways, in basement crawl spaces and the like, there is no predetermining just where the humidifier may be most accessible in any given installation. Therefore, with the present `invention it becomes practical for the first time to install the furnace as necessary, then select the best spot on almostany portion lof the furnace walls; back, sides, or front, in ducts, from furnace or returns to furnace, cut the required aperture and in a few minutes complete the whole installation including water connection, at precisely the best location for that speciiic heating plant.

Another defect of the prior art devices having the pan located in the warm air stream has been the excessive precipitation of lime compounds that often occurred in the pan which reduced to some extent the capillary action in the evaporating elements. In the normal opnited States atent Obviously it will be impossible to install a conventional huf 2,847,989 Patented Aug. 19, 1958 tial portion of such lime compounds as well as other compounds in solution will form precipitates and drop out. It is found that approximately degrees Fahrenheit is the upper limit of water temperature that can be used while having little, if any, precipitation of the compounds.

When using the conventional prior art humidifier units the evaporator pan is generally located in the air duct down stream from the heating unit so as to obtain the greatest humiditication of the air. The temperature of this air will always be well in excess of the upper limit of approximately 120 degrees Fahrenheit, and hence, there generally always will be -a great deal of undesirable precipitates formed in the pan. y

While we have explained how the present invention obviates the troubles from precipitation of foreignmatter in the water regardless of how highly heated the air may be inside the furnace at the point of installation on the furnace, there is a collateral advantage in the present invention, which may not be obvious. Heretofore, pan type humidiliers, even with evaporating plates, have had greatly reduced evaporating capacity when installed in a cold air return duct or in the bottom spaces of a furnace where air temperatures were relatively low. Consequently, the installer was instructed against using such points for installation. This difliculty arose from two causes, rst, cold air will not pick up as much moisture as hot air, and second, the pan obstructed most effective action of the plates regardless lof the air temperature. While the first factor still has its effect, the present invention completely eliminates all obstruction to the airow with the result that the plates are of maximum effectiveness at all times regardless of location. Therefore it becomes perfectly practicable to install our unit at any convenient location with the assurance of effective humidification of the passing air stream regardless of its temperature.

lt is an important object of the present invention to provide -a hurnidilier unit which will overcome these problems inherent in the prior art devices and which is constructed and arranged so that the evaporating pan will be located outside the airstream while the evaporating elements alone extend into such stream, thus, reducing to a minimum the obstruction to the air flow and at the same time preventing the pan and water contained therein from being heated by such air stream.

It is another object of the present invention to provide a humidifier unit of the foregoing character which is constructed and arranged so that it will -have more universal application whereby it can be installed and used with equal facility with any type of heating system, thereby enabling parts to be standardized and effecting more economical production and sale of such unit.

lt is still another object of the present invention to provide an air humidifier unit of the foregoing character which has an improved construction and arrangement for mounting the same on an air duct or the like, the mounting means being characterized by the ease with which the unit can be installed and maintained in position so that the most eliicient operation of the unit is obtained and so that heating of the water in the pan above the critical temperature of 120 degrees Fahrenheit is avoided.

It is still vanother object of the present invention to provide a humidifier unit of the foregoing character which has an improved float control mechanism so that the float chamber can be a minimum size while providing optimum flow control of water to the chamber.

It is still another object of the present invention to provide an improved evaporating plate or element for a humidifier unit, said element being shaped so that the optimum evaporation of water therefrom will occur while preventing dripping from its edges so that water will not be transferred from such plate to the adjacent air duct walls, thereby preventing rusting of the latter.

It is still another object of the present invention to provide an improved humidifier unit in which the water flow control mechanism and the means for supporting the evaporating elements are enclosed within the same chamber, thereby providing a lower cost unit by virtue of the reduced materials and labor required to make the same.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

In the drawings;

Figure 1 is a front elevation of a vhumidifier unit embodying our invention;

Figure 2 is a plan of the embodiment shown in Figure 1 with the cover for the same removed; and

Figure 3 is an enlarged section taken on the line 3 3 of Figure 1.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the inventionis capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring now to the drawings, a more detailed description of the present invention will be given. The humidifier unit is shown mounted on the side wall 12 of an air duct, furnace casing, or the like. The wall 12 has an aperture 14 cut therein which is closed by mounting the humidifier unit 10 thereover. For this purpose the humidifier unit 10 has a frame 16 which can be attached to the edges of the aperture 14 in wall 12 by means of any suitable fasteningfmeans such as the plurality of screws 18. Located on the upper side of the frame 16 are a pair of wing nuts 20 which are designed to hold a cover of the humidifier unit 10 in place, as will be explained later.

A relatively narrow shallow pan 22 forms the chamber for the float control mechanism 24 and for the rack l26 which carries the plurality of evaporating plates or elements 27; The float control mechanism 24 includes the elongated float 28, adapted to float on the surface of the water within pan 22, `which lioat is connected to one end of the essentially horizontally extending oat arm 30. An upward extension 32 of the float arm 30 is pivotally secured at 34 to the horizontal and axially movable pivot supporting shaft 36. The upper end of the extension 32 is pivotally secured at 38 to the horizontally movable plunger 40 which is movable to the left or right in Figure 1 for opening or closing the orifice of the water inlet in the duct 42 upon the falling or rising of float 28. The duct 42 is suitably connected to a source of water (not shown). The fioat 28 is preferably made as a relatively thin glass bulb, the thickness of theglass approximately that of a conventional light bulb. It may be connected to the float arm 24 by means of a resilient member carried in a reentrant throat portion of the tioat in the manner disclosed in greater detail in the copending application for patent of Powers, Serial No. 301,459, filed July 29, 1952, from which Letters Patent No. 2,753,886 was granted on July l0, 1956. By virtue of the elongated, narrow shape of the float 28 and its buoyancy resulting from its light weight and shape, the pan 22 can be relatively small in size while allowing optimum results by the float control mechanism 24 in controlling the flow of water into such pan 22.` Welded or secured in any other suitable fashion to the inner surface of pan 22 are a pair of support brackets 44 and 46 which carry the rack 26. The latter is formed preferably from sheet metal and has a plurality of upwardly looped arms 48 between which the evaporating plates 27 are carried.

The rear side of pan 22 has a rcversely turned lip 50 which overhangs the lower edge of the aperture 14 cut in the side wall 12 of the air duct or the like. In this manner the pan 22 together with its contents is supported directly from the side wall 12. In order to keep the pan from being warmed by the side wall 12 and also to maintain pan 22 level, tabs 52, Figure 3, are provided in the frame 16, such tabs holding the pan 22 in spaced relation from wall 12.

A Cover 54 is provided to close the open pan 22 as well as the aperture 14 in the side wall 12. A depending flange 56 fits inside. the upper ends of brackets 44 and 46 as best seen in Figure 3 with respect to bracket 44. The upper edge 58 fits against the side wall 12 within frame 16 so that the wing nuts 20 will secure the cover 54 as well as pan 22 and its contents in place when such wing nuts are turned to overlap cover 54, as is shown in Figure 1.

The evaporating elements 27 are in the general shape of an inverted L so that the leg portions can be supported by the rack 26 with their lower edges submerged in the water carried in pan 22. The outwardly extending wing portions project through the aperture 14 in the wall 12 into the warm air stream. By virtue of capillary action, water from pan 22 will be transmitted through the lateral surfaces of the evaporating elements 27 into the moving Warm air stream. The evaporating elements 27 may be made of any suitable material, but preferably are porous products of the type disclosed in the patent to Powers, No. 2,271,829, issued February 3, 1942.

It is highly desirable that the evaporating elements 27 be constructed so that water will not drip or run from their edges onto adjacent metallic surfaces which might then rust. Evaporating elements having the general shape shown in Figure 3 have proved to be very satisfactory in this respect. It will be noted that the lower edge of the wing portion is inclined at approximately 12 degrees to the horizontal, and the leg portion is notched or cut out at 60 so that the evaporating elements 27 cannot contact the pan 22 along the upper edge of the latter.

These are relatively important features of the evaporating elements 27. The inclined lower edge assures that the water will return through the evaporating elements 27 rather than drip therefrom when air is not flowing through the air duct. While greater angles than 12 degrees can be used, this would reduce the effective size of the elements 27, and therefore is not desirable. The notched portion at 60 assures that water will not run from the evaporating elements 27 over the edge of pan 22, and from there down the wall 12.

One of the important features of the humidifier unit described above is the ease and simplicity with which it can be installed. It is only necessary to determine the side of the furnace best suited for the humidifier and for servicing the same. The aperture 12 can then be cut in this location after which the frame 16 is installed, being certain that it is level since this controls the longitudinal levelness of the pan 22.

The lip 50 is then hooked over the bottom edge of the frame 16 and furnace casing opening. The pan 22 is leveled by adjusting the spacing of the tabs 52 at the bottom of frame 16. The inlet water conduits (not shown) can then be connected to the duct 42, and a similar overow conduit (not shown) can be connected to the duct 62. Thereafter, the cover 54 can be mounted in place and secured by the wing nuts 20 as previously described.

The float control apparatus for regulating the flow of water and the rack for holding the evaporating elements can be installed in the pan at the factory so the man in the field need not be concerned with this operation. The evaporating elements 27 are preferably installed in alternate slots in the rack 26 as is shown. In order to facilitate installing these elements so that they are properly centered and will not come into contact with one'or the other side edge of frame 16, the rack 26 can be moved longitudinally through brackets 44 and 46. Once the rack 26 has been centered with respect to the aperture 14 and frame 16, evaporating elements can be inserted in place adjacent to the upwardly extending tabs 64 thereby locking the rack 26 against longitudinal movement. The remainder of the evaporator elements can then be installed. Thus, it can be seen that a simple operation for installing the unit or gaining access to the same for servicing it is provided.

Another important feature of the present invention is the eicient manner in which the air is humidied. As best seen in Figure 3, only one pan is required rfor the unit and this pan is located outside the furnace casing or air duct so that it does not constitute an obstruction to the warm air ow. Thus, the air can flow freely against the side surfaces of the evaporating elements to provide the most effective scrubbing action possible, and there will be none of the undesirable eddy currents or dead air pockets around the evaporating elements as was so common-in prior art devices. Likewise, the water in the pan 22 will not be heated by the warm air stream so that the temperature of the water will normally remain below 120 degrees Fahrenheit, and as a result, no undesirable precipitates will form in the pan and in the lower portions of the evaporating elements so as to impair the capillary action that normally will occur in the latter. Furthermore, the fact that the water Vin the pan remains free of all collection of lime and similar precipitates, which heretofore has necessitated the provision of a separate water chamber for the valve and oat mechanisms in a cool location relatively remote from the heated evaporating pan, we are now able to combine the valve and oat pan, and the evaporating pan into a Single water area` This water area remains free of all deleterious accumulation o'f foreign matter, thus assuring long service, free functioning of the valve and fioat mechanism. In addition, as practically all lime is retained within and upon the evaporating plates themselves, and not within the pan, the simple act of replacing old plates with new ones is all that the homeowner needs to do. This completely obviates the time consuming and unpleasant job of chipping and scraping out the hard deposits from the pan heretofore necessary at least once each heating season. This operation in the hands of the homeowners using crude tools such as chisels, knives, and Scrapers has frequently resulted in damaging the glassy porcelain enamel coating of the water pan. This often happens without the operator being aware of what has occurred. As a direct result the life expectancy of the pan is greatly shortened as such points of damage act as focal points in rapid rusting and early failure from water leakage within the furnace and upon the basement door. Any such leakage of the water pan is obviously a major defect and from long experience in the field it has been found that even though the homeowner was careless in cleaning the pan and damaged the protective enamel, the actual leakage does not occur until several months later, and he claims is was defective when installed. From a practical point of view the only way to retain the customers good will is to install a complete new humidifier free of charge, and this occurs frequently and is a very costly procedure. In the present invention all this is obviated, and in addition accomplished with but a single water chamber.

From the foregoing description it will also be understood that the described embodiment of the invention can be used equally well with any type of warm air furnace. As the inwardly projecting distance of the evaporating plates through the aperture in the wall of the heating plant does not exceed 3 inches, and may be less, and as there is always considerable air space between the outer shell of the furnace and the heating element of the furnace (frequently partly occupied by an inner liner which is easily cut through), it is readily possible to install our humidifier atpractically any spot on the outer walls of the heating plant. Thus, it can be installed anywhere in the casing of a conventional up draft furnace or a counter flow furnace, a space heater, or it may be used in an air duct. Thus, it has more universal application than prior art devices enabling a more standardized product to be made. This in turn enables the same to be manufactured in larger quantities in a more economical manner.

Having thus described our invention, we claim:

1. A humidifier unit for mounting on an apertured upright side wall of an air duct in which air is directed in substantially a vertical stream comprising a vertically `disposed frame adapted to be secured to said wall on the external side thereof and over the edges of said aperture, a pan supported from said frame so as to extend lengthwise before the opening of the frame with the edge of the pan adjacent said frame being located below the level of the upper edge of the frame, two brackets mounted on the bottom of said pan in spaced relation and each having an upwardly extending tab, an elongated rack carried on said brackets in generally parallel relation to said frame and movable on the brackets in the lengthwise direction of the pan, said rack having transverse slots in its upper portion extending below the upper level of said tabs, a plurality of relatively rigid porous plates inserted in said slots, two of said plates fitting on opposite sides of said tabs to restrict lengthwise movement of said rack after insertion of said two plates, the upper portions of said plurality of relatively rigid porous plates projecting over the upper edge of said pan but below the upper edge ofV said frame with each plate having a projecting wing which is adapted to extend laterally into the air duct, means for regulating the flow of water into said pan, and a cover fitting over said pan and said plurality of plates and over the opening in said frame.

2. A humidifier unit for mounting on an apertured upright side wall of an air duct in which air is directed in substantially a vertical stream comprising a vertically disposed frame adapted to be secured to said wall on the external side thereof and over the edges of said aperture, a pan supported from said frame so as to extend lengthwise before the opening lof lthe frame with the edge of the pan adjacent said frame being located below the level of the upper edge of the frame, two brackets mounted on the bottom of said pan in spaced relation and each having an upwardly extending tab, an elongated rack carried on said brackets in generally parallel relation to said frame and movable on the brackets in the lengthwise direction of the pan, said rack having transverse slots in its upper portion extending below the upper level of said tabs, a plurality of relatively rigid porous plates inserted in said slots, two of said plates fitting on opposite sides of said l tabs to restrict lengthwise movement of said rack after insertion of said two plates, the upper portions of said plurality of relatively rigid porous plates, projecting over the upper edge of said pan but below the upper edge of said frame with each plate having a projecting wing which is adapted to extend laterally into the air duct, means within said pan for regulating the flow of water thereinto for contacting the lower ends of said plates, said means including a relatively long thin glass float and an aligned float arm, said float and float arm being generally parallel to said rack so that a pan of minimum width with respect to its length can be used, and a cover fitting over said pan and said plates and the opening in said frame.

3. A humidifier unit for mounting on an apertured upright side wall of an air duct in which air is directed in substantially a vertical stream comprising a vertically disposed frame adapted to be secured to said wall on the external side thereof and over the edges of said aperture, a pan supported from said frame so as to extend lengthwise before the opening of the frame with the edge of the pan adjacent said frame being located below the level of Y7 the upper edge of the frame, means extending lengthwise of said pan for supporting a plurality of relatively rigid porous plates in operating positions, said means being constructed and arranged so that the operating positions of the plates with respect to the frame and the number of plates used can be selectively determined at the time of installation, said plates being supported. over said pan in upright parallel spaced relationship with their lower ends withinthe pan and adjacent the bottom thereof, the upper portions of said plates projecting over the Upper edge of said pan but below the upper edge of said frame with each plate having a projecting wing which is adapted to extend laterally into the air duct,'thel projecting wings of said plates being the sole portion of the humidifier unit extending beyond'the inner side of the frame so that the humidier unit is adapted to cause substantially no impedance to air flow in said air duct, said pan being supported from said frame by an overhanging lip formed integrally with said adjacent edge of the pan, said overhanging lip being hooked over the lower edge of said frame, said frame having an outwardly deflected tab contacting the side of said pan for keeping said pan out of contact with the wall of said air duct, means within said pan for regulating the flow of water thereinto for contacting the lower ends of said plates, anda cover fitting over said pan and said plates and over the opening in said frame.

4. A humidifier unit for mounting on an apertured upright side wall of an air duct in which air is'directed in substantially a vertical stream comprising a vertically disposed frame adapted to be secured to said wall on the external side thereof and over the edges of said aperture, a pan supported from said frame so as to extend lengthwise before the opening of the frame with the edge of the pan adjacent said frame being located below the level of the upper edge of the frame, two brackets mounted on the bottom of said pan in spaced relation and each having an upwardly extending tab, an elongated rack carried on said brackets in generally parallel relation to said frame and movable on the brackets in the lengthwise direction of the pan, said rack having transverse slots in its upper portion extending below the upper level of said tabs, a plu- Cil rality of relatively rigid porous plates inserted in said slots, two of said plates fitting on opposite sides of said tabs to restrict lengthwisefmovement of said rack after insertion lof said two plates, the upper portions of saidplurality of relatively rigid porous plates projecting over the upper edge of said pan but below the upper edge of said frametwith each'plate having a projecting wing which is adapted to extend laterally into the air duct, said pan being supported from said frame by anv overhanging lip formed'integrally with said adjacent edge of the pan, said overhanging lip being hooked over the lower edge of said frame, said frame having an outwardly deflected tab contacting the side of said pan for keeping said pan out of contact with the wall of said air duct, means within `said pan for regulating the flow of water thereinto for contacting the lower ends of said plates, and a cover fitting over said pan and said plates and over the opening in said frame.

5. A humidifier as claimed in claim 4 wherein said means for regulating the ow of water into said pan includes a relatively long thin tloat and an aligned float arm, said float and oat arm being generally parallel to said rack so that a pan of minimum width with respect to its length can be used.

References Cited in the file of this patent UNITED STATES PATENTS 1,116,861 Wilson Nov. 10, 1914 1,817,357 Fisher Aug. 4, 1931 1,879,358 Lilly Sept. 27, 1932 2,158,543 Jensen May 16, 1939 2,394,698 Kuenhold Feb. 12, 1946 2,565,210 Dovolis Aug. 21, 1951 2,569,512 Bottum Oct. 2, 1951 2,585,764 Getz Feb. 12, 1952 2,651,293 Bottum Sept. 8, 1953 2,678,235 Perlman May 11, 1954 FOREIGN PATENTS 2,723 Great Britain Feb. 19, 1915 

